Question

I’m trying to design some images and button images for an Android app. But there are so many screen sizes and DPI settings.

Can someone explain me what are screen sizes and DP means? and a simple way to design images to fit all devices (if possible)

Thanks

Sample 9-patch images i did.

Answer 1

Yes i would suggest you to go through below article first, you will come to know everything about Screen resolutions and dp.

Supporting Multiple Screens

And now here is a best explanation about Icon Design Guidelines.

DP means density independent pixel, which is more preferable to depict measurement (As compared to PX) for any views.

From above document:

• A set of four generalized sizes: small, normal, large, and xlarge
• A set of four generalized densities: ldpi (low), mdpi (medium), hdpi (high), and xhdpi (extra high)

One more thing to keep in mind:

To create alternative bitmap drawables for different densities, you should follow the 3:4:6:8 scaling ratio between the four generalized densities. For example, if you have a bitmap drawable that’s 48×48 pixels for medium-density screen (the size for a launcher icon), all the different sizes should be:

36x36 for low-density
48x48 for medium-density
72x72 for high-density
96x96 for extra high-density

Button images: OR 9-patch images

To create background and selector images for button, i would suggest you to create 9-patch image, you can create 9-patch image using 9-patch tool. If you create 9-patch image then it will grow and shrink according to the height/width of any view and its doesn’t looks ugly.

Example of 9-patch images are:

Nice Collections of 9-patch images: http://android9patch.blogspot.com/2011/10/android-9-patch-pack-22-more-buttons.html